OneDrive behaves quite a bit differently in W7 than it does in W10. Don't know if those fixes Jack gave you will work or not with your system, but it's worth trying.
I would recommend that you should first backup all your personal data on that computer to external media to avoid irretrievable data loss before proceeding!
In the case that neither of Jack's W10 repairs fix your problem and restore your missing files, you should then attempt a System Restore. Of course that assumes that at some point since you owned your computer, you went in and manually enabled it; in W7/W8x/W10 it comes from Microsoft as DISABLED. If you did enable it, you can attempt the System Restore and and see if it will put your OneDrive files...